Splachnaceae is a family of mosses, containing around 70 species in 6 genera. Around half of those species are entomophilous, using insects to disperse their spores, a characteristic found in no other seedless land plants.
Many species in this family are coprophilous, growing exclusively on animal faeces or carrion. For this reason, certain genera such as Splachnum Hedw. are often referred to as dung mosses.
Description
Mosses in this family are predominantly dioicous (archegonia and antheridia on separate individuals); although exceptions are known such as S. pensylvanicum which is monoicous. The gametophyte is always acrocarpous (standing up), with green-yellow to reddish leaves/stems, and most often under 5 cm in height. Stems stand vertically and when cross-sectioned, can be seen to have a well-defined central strand. Large parenchymatous cells surround the central strand with thin, red to orange cell walls. Cortical cells are often more red in color, being narrow and thick-walled. Axillary hairs may be present along the stem, although axillary branches are infrequent. Rhizoids are dark brown or red and may be papillose.
Female plants are more robust than male plants; having spreading, ovate to lanceolate leaves that are moderately crisped when dry. Leaf distribution may be homogenous or may become larger/denser near the apex of the stem. Leaves may be serrate (finely toothed) on the edges, and possess a single costa that often ends before the apex. Laminal cells are thin-walled, being more rectangular towards the base and hexagonal at the apex. Perichaetial leaves are often larger, but similar in structure to the other leaves on the stem.
Illustration of the sporophytic and gametophytic stages of Splachnum ampullaceum
Male plants are more slender, with a looser leaf distribution. Leaves differ in size and differentiation towards the apex of the stem forming an often-bulbous perigonia. Perigonial leaves are strongly differentiated, being ovate and...
